The NAACP now presents itself as a counterbalance to the influence of the traditionally socially conservative black church. It can also help establish closer ties between blacks and gays, two of Obama's most loyal constituencies.

Some pro-Republican conservative evangelical activists have said Obama's announcement gives them an unusual opportunity to deflate enthusiasm among black voters for reelecting the country's first black president, who tends to win more than 90 percent support in that community.

“Civil marriage is a civil right and a matter of civil law,” NAACP president Benjamin Todd Jealous said in a statement released Saturday. “The NAACP's support for marriage equality is deeply rooted in the Fourteenth Amendment of the United States Constitution and equal protection of all people. The well-funded right wing organizations who are attempting to split our communities are no friend to civil rights, and they will not succeed.”

According to a tweet from Maxim Thorne, an NAACP officer, only two people out of the 64-member board of directors voted against the resolution, which states: "The NAACP Constitution affirmatively states our objective to ensure the 'political, education, social and economic equality' of all people. Therefore, the NAACP has opposed and will continue to oppose any national, state, local policy or legislative initiative that seeks to codify discrimination or hatred into the law or to remove the Constitutional rights of LGBT citizens. We support marriage equality consistent with equal protection under the law provided under the Fourteenth Amendment of the United States Constitution. Further, we strongly affirm the religious freedoms of all people as protected by the First Amendment."